Method for making a polymeric based carpet

ABSTRACT

Polymeric carpet and a method of making and recycling such carpet, the carpet having fibers, backing and extruded adhesive all of completely recyclable materials, the recycling being accomplished in one melting step, without a separation step.

FIELD OF THE INVENTION

[0001] The present invention relates to a polymeric based carpet.

BACKGROUND OF THE INVENTION

[0002] It is desired in the textile industry to create products that are100 percent recyclable with minimum difficulty. Today's commerciallyprovided carpet products are predominantly manufactured using a latexbased binder to adhere the backing scrim to the carpet fibers. Thepurpose of the scrim and latex are to bind the carpet fibers and preventthe fibers from becoming unwoven or loose. The latex is undesirable froma recycling point of view. In order to reclaim the carpet fibers andscrim, which are normally polypropylene, polyester, or polyamide based,the latex has to be separated from the total composite.

[0003] A method of making and recycling carpet of all recyclablematerial has been disclosed. The disclosed carpet includes a primarybacking having tufts of synthetic carpet fibers protruding from a topsurface and, optionally, a secondary backing, with an extruded sheet ofan isotactic polyolefin polymer between and integrally fused to a bottomsurface of the primary backing and an upper surface of the secondarybacking. The isotactic polyolefin polymers shown to be effective to fusethe carpet fibers and the secondary backing in the disclosure areisotactic polypropylene and extruded blends of polypropylene withpolyethylene, polybutylene and thermoplastic elastomers. The previousdisclosures teach that polyethylene copolymers alone are a poor choicefor such a fusion material. Furthermore, it has been disclosed that ifanything other than polypropylene is used for the face fiber, extrudedsheet and secondary back, that the bonding of the materials must bephysically separated before recycling can take place.

[0004] In contrast, in the present invention, the use of ethylene methylacrylate copolymers as such a fusion material replacement for latexconventionally used to bind carpet fibers to backing material not onlyeliminates the need for a separation recovery process but also enhancesthe total products' performance when recycled. Furthermore, such acopolymer has advantages over polypropylene and the variouspolypropylene blends previously disclosed.

SUMMARY OF THE INVENTION

[0005] The present invention relates to a carpet composition, recyclablewithout a separation step, having from 50 to 100 percent polymericmaterial comprising:

[0006] a) a tufted primary backing having a primary backing and tufts ofcarpet fibers penetrating a bottom surface of the primary backing andprotruding from a top surface of the primary backing;

[0007] b) a secondary backing material; and

[0008] c) an extruded adhesive material or a coextrusion of two or moreextruded adhesive materials binding an upper surface of the secondarybacking material to the bottom surface of the primary backing;

[0009] in which the carpet fibers, primary backing material andsecondary backing material are selected from the group consisting ofpolypropylene, polyester, acrylics, polyethylene, polyamide, nylon,wool, cotton, rayon and combinations thereof;

[0010] and in which the adhesive material comprises an amorphouspolyethylene copolymer selected from the group consisting of ethylenemethyl acrylate, ethylene normal butyl acrylate, and blends of two ormore polyethylene copolymers.

[0011] In a preferred embodiment, the extruded adhesive material of theabove described carpet composition comprises a middle layer ofpolyethylene sandwiched between two outer layers selected from the groupconsisting of ethylene methyl acrylate and ethylene normal butylacrylate.

[0012] In a more preferred embodiment, the middle polyethylene layer ofthe above described extruded adhesive material is from 10 to 90 weightpercent of the extruded adhesive material and each of the two outerlayers is from 5 to 45 weight percent of the extruded adhesive material.

[0013] In another preferred embodiment, the adhesive material of theabove described carpet composition further comprises maleic anhydride.

[0014] In yet another preferred embodiment, the adhesive material of theabove described carpet composition is a coextruded blend of ethylenemethyl acrylate copolymers and polymers selected from the groupconsisting of low density polyethylenes, linear low densitypolyethylenes, high density polyethylenes, ultra low densitypolyethylene having a density less than 0.915 density,ethylene-propylene copolymers, elastomers, rubber, EPDM (ethylenepropylene diene monomer) rubber, styrenic copolymers of butadiene,styrenic copolymers of acrylonitrile, styrenic copolymers of ethylene,metallocene based polyethylenes, polypropylene, polyester, ethyleneacrylic acid copolymers, ethylene methyl acrylic acid copolymers, butylacrylate copolymers, ethylene vinyl acetate copolymers, ionomers,polyamides, and maleic anhydrides.

[0015] In still another preferred embodiment, the adhesive material ofthe above described carpet composition has a thickness of from 0.001inches to 0.050 inches.

[0016] In yet another preferred embodiment, the adhesive material of theabove described carpet composition further comprises additives selectedfrom the group consisting of flame retardants, odor reduction additives,scent enhancing additives and ultra-violet light protection additives.

[0017] In still another preferred embodiment, the adhesive material ofthe above described carpet composition further comprises fillersselected from the group consisting of talc, calcium carbonate and otherinorganic fillers.

[0018] The present invention also relates to a method of making acarpet, the carpet comprising a tufted primary backing with a primarybacking and tufts of carpet fibers penetrating a bottom surface of theprimary backing and protruding from a top surface of the primarybacking; a secondary backing material; and an adhesive material bindingan upper surface of the secondary backing material to the bottom surfaceof the tufted primary backing; the carpet fibers, primary backingmaterial and secondary backing material being selected from the groupconsisting of polypropylene, polyester, acrylics, polyethylene,polyamide, nylon, wool, cotton, rayon and combinations thereof and theadhesive material comprising an amorphous polyethylene copolymerselected from the group consisting of ethylene methyl acrylate andethylene normal butyl acrylate; the method comprising the steps of:

[0019] a) extruding a heated sheet of the adhesive material; and

[0020] b) continuously fusing together in a two roll nip the uppersurface of the secondary backing and the bottom surface of the tuftedprimary backing with the heated sheet.

[0021] In a preferred embodiment of the above described method, the tworoll nip comprises a hard roll and a soft roll.

[0022] In a more preferred embodiment of the above described method, thesoft roll has a diameter of from 4 to 20 inches and a hardness of from 5to 100 shore D.

[0023] In another more preferred embodiment of the above describedmethod, the soft roll is comprised of rubber.

[0024] In still another more preferred method, the hard roll is a cooledmetal chill roll capable of maintaining a temperature below 120° F.

[0025] In yet another more preferred method, the two roll nip haspressure between 20 and 200 pounds per linear inch.

[0026] The present invention also relates to a method of using at leastone of ethylene methyl acrylate copolymer and ethylene normal butylacrylate copolymer to manufacture a carpet, the carpet comprising atufted primary backing with a primary backing and tufts of carpet fiberspenetrating a bottom surface of the primary backing and protruding froma top surface of the primary backing; a secondary backing material; andan adhesive material binding an upper surface of the secondary backingmaterial to the bottom surface of the tufted primary backing; the carpetfibers, primary backing material and secondary backing material beingselected from the group consisting of polypropylene, polyester,acrylics, polyethylene, polyamide, nylon, wool, cotton, rayon andcombinations thereof and the adhesive material comprising an amorphouspolyethylene copolymer selected from the group consisting of ethylenemethyl acrylate and ethylene normal butyl acrylate; the methodcomprising the steps of:

[0027] a) extruding a heated sheet of the adhesive material; and

[0028] b) continuously fusing together in a two roll nip the uppersurface of the secondary backing and the bottom surface of the tuftedprimary backing with the heated sheet.

[0029] In a preferred embodiment of the above described method, the tworoll nip comprises a hard roll and a soft roll.

[0030] In a more preferred embodiment of the above described method, thesoft roll has a diameter of from 4 to 20 inches and a hardness of from 5to 100 shore D.

[0031] In another more preferred embodiment of the above describedmethod, the soft roll is comprised of rubber.

[0032] In still another more preferred embodiment of the above describedmethod, the hard roll is a cooled metal chill roll capable ofmaintaining a temperature below 120° F.

[0033] In yet another more preferred embodiment of the above describedmethod, the two roll nip has pressure between 20 and 200 pounds perlinear inch.

[0034] The present invention also relates to a method of recycling acarpet, the carpet comprising a tufted primary backing with a primarybacking and tufts of carpet fibers penetrating a bottom surface of theprimary backing and protruding from a top surface of the primarybacking; a secondary backing material; and an extruded adhesive materialor a coextruded blend of two or more extruded adhesive materials bindingan upper surface of the secondary backing material to the bottom surfaceof the primary backing; the carpet fibers, primary backing material andsecondary backing material being selected from the group consisting ofpolypropylene, polyester, acrylics, polyethylene, polyamide, nylon,wool, cotton, rayon and combinations thereof and the adhesive materialcomprising an amorphous polyethylene copolymer selected from the groupconsisting of ethylene methyl acrylate and ethylene normal butylacrylate; the method comprising the step of melting the carpet to obtainan extrudate feedstock.

DETAILED DESCRIPTION OF THE INVENTION

[0035] A novel composite and process has been invented which creates a50 to 100 percent polymeric product which allows it to be recycled. Thecomposite can provide water-resistant properties heretofore impossiblewith latex bound carpet products. In addition, the new product canincorporate performance-enhancing additives such as flame-retardants,odor reduction additives, scent-enhancing additives, ultra-violet lightprotection additives and inorganic materials, such as talc and calciumcarbonate, for cost reduction and strength properties. It has also beenfound that when calcium carbonate is added as a filler, it functions asa “heat sink”, i.e., it lets the polymer blend stay hot longer duringthe manufacturing process. This has the effect of improving thepenetration of the polymer into the carpet fibers.

[0036] With the use of ethylene methyl acrylate based copolymers, thecarpet can now be ground and reprocessed with no interim step to removeincompatible materials. When incorporated with polypropylene, polyesterand polyamide polymers, methyl acrylate copolymers act as acompatibilizer to cause the new blend to adhere to itself in anysubsequent fabrication process.

[0037] The use of ethylene methyl acrylate copolymers as a replacementfor latex conventionally used to bind carpet fibers to backing materialnot only eliminates the need for a separation recovery process but alsoenhances the total products' performance when recycled. The ethylenemethyl acrylate material serves as a binder for the reclaimed product aswell as improving the impact resistance and pliability of the secondaryproduced product.

[0038] In addition to the novel materials used in the new composite,certain processing techniques are employed that guarantee the properlevel of adhesion is obtained in the laminate. These techniques a rubbernip roll with a diameter of 4 to 20 inches, and a hardness of 50 to 100shore D. A water-cooled metal chill roll capable of maintaining atemperature below 120° F. The pressure of the rubber to steel nip isbetween 40 and 200 pounds per linear inch. Extrudate temperaturesgreater than 550° F. is preferred.

EXAMPLES

[0039] The invention will be further illustrated by the followingexamples, which set forth particularly advantageous method embodiments.While the Examples are provided to illustrate the present invention,they are not intended to limit it.

Example 1

[0040] Various samples of carpet were manufactured having tufts ofpolypropylene interwoven in a primary backing of polypropylene with anextruded sheet of ethylene methyl acrylate copolymer sandwiched to thebottom of the primary backing and the top of a secondary backing ofpolypropylene. The carpets were made in two different weave styles andat various extrudate speeds and temperatures. The Fiber Lock and TuftBind tests were applied to the samples and were scored with Pass (P),Marginal (M) or Fail (F) scores. The results are shown in Table 1. TABLE1 Style Temperature Speed Fiber Lock Score Seacroft 575 100 MarginalSeacroft 575 75 Pass Seacroft 575 50 Pass Seacroft 600 75 Pass Glasgow575 100 Pass Glasgow 575 75 Pass Glasgow 575 50 Pass Glasgow 600 75 Pass

Example 2

[0041] Various samples of carpet were manufactured having tufts ofpolypropylene interwoven in a primary backing of polyamide with anextruded sheet of ethylene methyl acrylate copolymer sandwiched to thebottom of the primary backing and the top of a secondary backing ofpolyamide. The carpets were made in different weave styles and atvarious extrudate thicknesses and temperatures. The Fiber Lock and TuftBind tests were applied to the samples and were scored with Pass (P),Marginal (M), or Fail (F) scores. The results are shown in Table 2.TABLE 2 Extrudate Extrudate Fiber Lock Tuft Bind Style Temp. ThicknessScore Score (lb.) Sample 1 575 5.0 mils Fail 6.0 Sample 1 575 7.5 milsFail 8.0 Sample 1 575  10 mils Pass 8.5 Sample 1 600 7.5 mils Marginal8.0 Heavier wt. Level loop - Polyamide Sample 2 575 5.0 mils Marginal9.0 Sample 2 575 7.5 mils Pass 8.5 Sample 2 575  10 mils Pass 8.0 Sample2 600 7.5 mils Marginal 10.5 Sample 3 575 5.0 mils Pass 8.0 Sample 3 5757.5 mils Pass 12.0 Sample 3 575  10 mils Pass (much better) 10.0 Sample3 600 7.5 mils Pass N/A Textured Level loop - Polyamide Sample 4 575 5.0mils Marginal 10.0 Sample 4 575 7.5 mils Pass 12.0 Sample 4 575  10 milsPass 10.0 Sample 4 600 7.5 mils Pass 10.0 Polyamide Sample 5 575 5.0mils Fail 10.0 Sample 5 575 7.5 mils Fail 10.0 Sample 5 575  10 milsMarginal 8.0 Sample 5 600 7.5 mils Marginal 8.0 26 oz. P.A. Level loop -Polyamide Sample 6 575 5.0 mils Fail 9.5 Sample 6 575 7.5 mils Marginal10.0 Sample 6 575  10 mils Pass 6.0 Sample 6 600 7.5 mils Marginal 8.0Polyamide Sample 7 575 5.0 mils Marginal 8.5 Sample 7 575 7.5 mils Pass10.5 Sample 7 575  10 mils Pass 12.0 Sample 7 600 7.5 mils Pass 12.0Level loop - Polyamide Sample 8 575 5.0 mils Pass N/A Sample 8 575 7.5mils Pass N/A Sample 8 575  10 mils Pass N/A Sample 8 600 7.5 mils PassN/A Cut pile - Polyamide

[0042] While the present invention has been described with reference tospecific embodiments, this application is intended to cover thosevarious changes and those skilled in the art may make thosesubstitutions without departing from the spirit and scope of theappended claims.

What is claimed is:
 1. A carpet composition, recyclable without aseparation step, having from 50 to 100 percent polymeric materialcomprising: a) a tufted primary backing having a primary backing andtufts of carpet fibers penetrating a bottom surface of the primarybacking and protruding from a top surface of the primary backing; b) asecondary backing material; and c) an extruded adhesive material or acoextrusion of two or more extruded adhesive materials binding an uppersurface of the secondary backing material to the bottom surface of theprimary backing; wherein the carpet fibers, primary backing material andsecondary backing material are selected from the group consisting ofpolypropylene, polyester, acrylics, polyethylene, polyamide, nylon,wool, cotton, rayon and combinations thereof; and wherein the adhesivematerial comprises an amorphous polyethylene copolymer selected from thegroup consisting of ethylene methyl acrylate, ethylene normal butylacrylate, and blends of two or more polyethylene copolymers.
 2. Thecarpet composition of claim 1 wherein the extruded adhesive materialcomprises a middle layer of polyethylene sandwiched between two outerlayers selected from the group consisting of ethylene methyl acrylateand ethylene normal butyl acrylate.
 3. The carpet composition of claim 2wherein the middle polyethylene layer of the extruded adhesive materialis from 10 to 90 weight percent of the extruded adhesive material andeach of the two outer layers is from 5 to 45 weight percent of theextruded adhesive material.
 4. The carpet composition of claim 1 whereinthe adhesive material further comprises maleic anhydride.
 5. The carpetcomposition of claim 1 wherein the adhesive material is a coextrudedblend of ethylene methyl acrylate copolymers and polymers selected fromthe group consisting of low density polyethylenes, linear low densitypolyethylenes, high density polyethylenes, ultra low densitypolyethylene having a density less than 0.915 density,ethylene-propylene copolymers, elastomers, rubber, EPDM rubber, styreniccopolymers of butadiene, styrenic copolymers of acrylonitrile, styreniccopolymers of ethylene, metallocene based polyethylenes, polypropylene,polyester, ethylene acrylic acid copolymers, ethylene methyl acrylicacid copolymers, butyl acrylate copolymers, ethylene vinyl acetatecopolymers, ionomers, polyamides, and maleic anhydrides.
 6. The carpetcomposition of claim 1 wherein the adhesive material has a thickness offrom 0.001 inches to 0.050 inches.
 7. The carpet composition of claim 1wherein the adhesive material further comprises additives selected fromthe group consisting of flame retardants, odor reduction additives,scent enhancing additives and ultra-violet light protection additives.8. The carpet composition of claim 1 wherein the adhesive materialfurther comprises fillers selected from the group consisting of talc,calcium carbonate and other inorganic fillers.
 9. A method of making acarpet, the carpet comprising a tufted primary backing with a primarybacking and tufts of carpet fibers penetrating a bottom surface of theprimary backing and protruding from a top surface of the primarybacking; a secondary backing material; and an adhesive material bindingan upper surface of the secondary backing material to the bottom surfaceof the tufted primary backing; the carpet fibers, primary backingmaterial and secondary backing material being selected from the groupconsisting of polypropylene, polyester, acrylics, polyethylene,polyamide, nylon, wool, cotton, rayon and combinations thereof and theadhesive material comprising an amorphous polyethylene copolymerselected from the group consisting of ethylene methyl acrylate andethylene normal butyl acrylate; the method comprising the steps of: a)extruding a heated sheet of the adhesive material; and b) continuouslyfusing together in a two roll nip the upper surface of the secondarybacking and the bottom surface of the tufted primary backing with theheated sheet.
 10. A method according to claim 9 wherein the two roll nipcomprises a hard roll and a soft roll.
 11. A method according to claim10 wherein the soft roll has a diameter of from 4 to 20 inches and ahardness of from 5 to 100 shore D.
 12. A method according to claim 10wherein the soft roll is comprised of rubber.
 13. A method according toclaim 10 wherein the hard roll is a cooled metal chill roll capable ofmaintaining a temperature below 120° F.
 14. A method according to claim11 wherein the two roll nip has pressure between 20 and 200 pounds perlinear inch.
 15. A method of using at least one of ethylene methylacrylate copolymer and ethylene normal butyl acrylate copolymer tomanufacture a carpet, the carpet comprising a tufted primary backingwith a primary backing and tufts of carpet fibers penetrating a bottomsurface of the primary backing and protruding from a top surface of theprimary backing; a secondary backing material; and an adhesive materialbinding an upper surface of the secondary backing material to the bottomsurface of the tufted primary backing; the carpet fibers, primarybacking material and secondary backing material being selected from thegroup consisting of polypropylene, polyester, acrylics, polyethylene,polyamide, nylon, wool, cotton, rayon and combinations thereof and theadhesive material comprising an amorphous polyethylene copolymerselected from the group consisting of ethylene methyl acrylate andethylene normal butyl acrylate; the method comprising the steps of: a)extruding a heated sheet of the adhesive material; and b) continuouslyfusing together in a two roll nip the upper surface of the secondarybacking and the bottom surface of the tufted primary backing with theheated sheet.
 16. A method according to claim 15 wherein the two rollnip comprises a hard roll and a soft roll.
 17. A method according toclaim 16 wherein the soft roll has a diameter of from 4 to 20 inches anda hardness of from 5 to 100 shore D.
 18. A method according to claim 16wherein the soft roll is comprised of rubber.
 19. A method according toclaim 16 wherein the hard roll is a cooled metal chill roll capable ofmaintaining a temperature below 120° F.
 20. A method according to claim17 wherein the two roll nip has pressure between 20 and 200 pounds perlinear inch.
 21. A method of recycling a carpet, the carpet comprising atufted primary backing with a primary backing and tufts of carpet fiberspenetrating a bottom surface of the primary backing and protruding froma top surface of the primary backing; a secondary backing material; andan extruded adhesive material or a coextruded blend of two or moreextruded adhesive materials binding an upper surface of the secondarybacking material to the bottom surface of the primary backing; thecarpet fibers, primary backing material and secondary backing materialbeing selected from the group consisting of polypropylene, polyester,acrylics, polyethylene, polyamide, nylon, wool, cotton, rayon andcombinations thereof and the adhesive material comprising an amorphouspolyethylene copolymer selected from the group consisting of ethylenemethyl acrylate and ethylene normal butyl acrylate; the methodcomprising the step of melting the carpet to obtain an extrudatefeedstock.